1. Field of the Invention
The present invention relates to an image forming apparatus capable of executing a plurality of different functions.
2. Discussion of the Background
A multiplex copier having various functions including a copy function, facsimile function, printer function and file function is available today. This type of copier is designed to execute, among various modes, predetermined modes matching the condition in which the copy function is used. While modes of one function are operative, modes of the other functions are held inoperative. For example, assuming a multiplex copier with a copy function and a facsimile function, there are available a function of switching the print mode to a receive print mode meant for facsimile when the copy function is left unused more than a predetermined period of time and received facsimile data is present, or when a person is absent in front of the copier as determined by operating sensing means and received facsimile data is present. Further, the multiplex copier may be constructed to print document files received from system equipment or to use an optical disk drive as a filing unit.
A convention image forming apparatus having a copy function, facsimile function, printer function and file function as well as other functions has only a single controller. Specifically, the state of the art image forming apparatus with such functions cannot print data with a single laser printer shared by a plurality of functions, to print document files received from a plurality of system equipment by a single laser printer, or to print a plurality of files received by a plurality of facsimile sections by a single laser printer. While an image forming apparatus capable of printing data with a single laser printer shared by a plurality of functions via a network is available, even such an apparatus cannot print data by the laser printer except with a single function.
The multiplex copier allows various functions, i.e., copy function, facsimile function, printer function and file function to exist at the same time and allows each of them to execute a print mode, document read mode and other modes within itself. However, the fact that while the modes of one function are operative, the modes of the other functions are held inoperative as previously mentioned brings about the following problems. Assume that a facsimile section has received data at the time when a person intending to copy documents is about to operate the copier. Then, the facsimile data begins to be printed immediately to prevent the person from copying the documents. Conversely, data received by the facsimile section while a copying operation is under way cannot be printed. Further, assume that the operator continuously registers or files a great number of documents at a photomagnetic disk via a photomagnetic disk drive by using a scanner. Then, data received by the facsimile section cannot be printed until the filing operation ends.
Another problem with the multiplex copier is that while document files received from system equipment are sequentially printed, the other functions, e.g., copy function and facsimile function, are simply left unused. Many of document files to be received from system equipment have several hundred leaves to several thousand leaves, preventing the other functions from being used over a long period of time.
Likewise, the image forming apparatus having only a single controller cannot print document files received from system equipment while the laser printer is printing document files received from another system equipment. Further, this type of image forming apparatus cannot print files received by a facsimile section while the laser printer is printing files received by another facsimile section.